The sagittal configuration and mobility of the spine in idiopathic scoliosis.

The aim of this study is to see how the spinal sagittal configuration and mobility in 127 patients with idiopathic scoliosis are influenced by increasing scoliotic deformity and to determine when this deformity gets clinically significant compared to controls (n = 92). In patients with thoracic curves the degrees of thoracic kyphosis and lumbar lordosis were significantly less than those of the controls. Neither the kyphosis nor the lordosis were correlated to the Cobb angles. Even patients with small curves have straight spines in the sagittal plane; there is no tendency for the kyphosis and lordosis to decrease when the scoliotic deformity increases. This indicates that it is especially individuals with straight spines in the sagittal plane who are prone to develop scoliosis. It is also suggested that the limitation in spinal function for curves with Cobb angles below 50 degrees may be neglected.